Automatic belt-tightener



-G. N. GODDARD AND F. A. SMITH.

AUTOMATIC BELT TIGHTENER.

APPLICATION FILED SEPT. 15, 1919.

Patented July 26, 1921.

3 SHEETS-SHEET 1- G. N. GODDARD AND F; A. SMlTH.

AUTOMATIC BELT TIGHTENER.

APPLICATION FILED SEPT. 15. 1919.

1,385,942, PatentedJuly 26, 1921.

3 SHEETS-SHEET 2- G. N. GODDARD AND F. A. SMITH.

AUTOMATIC BELT TIGHTENER.

APPLICATION man SEPT. 15. 1919.

Patented July 26, 1921.

3 SHEETS-SHFET 3.

GEORGE N. GODDARD, OF NEXT/TON, AND F SETTS, ASSIGNORS 'lO AMERICAN TOOLBANK A. SMITH, OF READING, MASSACHU- & MACHINE COMPANY, GHUSETTS, ACORPORATION OF MASSACHUSETTS.

OF BOSTON, MASSA- Application filed September 15, 1919.

T0 aZZ whom it may concern:

e it known that we, GEORGE N. GODDARD, a resident of Newton, in thecounty of Mid dlesex and Commonwealth of Massachusetts, and FRANK A.SMITH, a resident of Reading, in the county of Middlesex andCommonwealth of Massachusetts, both citizens of the United States, haveinvented certain new and useful Improvements in Automatic Belt-Tighteners, of which the following is a specification. r This inventionrelates to belt tighteners for use in automatically taking up the slackor stretch of driving belts and is herein shown and described in itsapplication to the driving belt of a centrifugal machine.

The object of the invention is to produce a device of this kind whichshall be absolutely reliable and certain in its normal op eration andwhich shall be capable of quick and easy adjustment into inoperativeposition for the purpose of permitting easy access to substitute a newbelt or re-lace an old belt with suitable provision for positivelylocking the mechanism during such operation of substitution or re-lacingso as to avoid all danger of trouble or injury that might occur from theaccidental release of the tightener before thebelt is ready to 0perate.

To this end the invention comprises essentially a weighted lever havinga direct single link connection with the movable arm supporting theidler pulley which keeps the belt taut, said link and the pulleysupporting frame being formed to have a two-fold interlocking engagementwith each other in combination with a detachable latch for holding theweight-arm against normal operative movement.

This and other features of the invention will be more particularlydescribed in the following specification and will be defined in theclaims hereto annexed.

In the accompanying drawings is illustrated, the preferred formembodying the principles of this invention in which:

Figure 1 is a side elevation of the belt tightener mechanism in itsrelation to the driving belt of a centrifugal machine' Fig. 2 is a planview thereof.

Fig. 3 is a detail of the weight-arm link and latch construction intheir normal po- Speeification of Letters Patent.

Patented July 26-, 1921. Serial No. 323,917.

of the part shown in Fig. 7 is a detail view showing the locking latchand dog.

Fig. 8 is aside elevation ofthe link, weight arm and the latch showingthe parts locked in inoperativeposition. Y

In the practice of theinvention according to the form illustrated inthedrawings the tension or idler pulley a is mounted in adjustable boxes aat theupper ends of the 'swinging frame which supports the pulleycomprising two substantially parallel vertical arms a provided at theirupper ends with suitable slots o to receive the adjustable boXes bywhich the pulley is rotatably supported. This frame is pivoted at itslower end to'suitable blocks attached to the floor or platform as shownat a. The belt 6 is shown passing over the idler tension pulley a fromthe driving pulley I), to the driven pulley b of the centrifugal.

The two arms a of the frame are connected a short distance below thepulley by the crossbar a which serves as a support for the pivotal latchmember f and which also forms the engaging member with the connectinglink 6 as will be hereinafter explained.

On a suitable bracket or support 0 is pivoted a weight-lever a carryingat its outer free end preferably a weight ciand having I a shortangularly projecting arm 0 The intermediate portion of this lever isprovided with a slot at c in which is adjustably secured a pin 0 whichis so located in the slot 0 as to be engaged. by the latchv f to holdthe weight-arm against dropping of its own weight in order to render theweight-arm temporarily inoperative. V

The short arm 0 of the weight arm is pivotally connected at c with aconnecting link 6 whose forward end is provided with a slot formed atits two ends with notches or recesses 6 6 This .slot e receives orincloses the cylindrical cross-bar a of the swinging idler pulley framewhich is adapted in order to with either to fit into both notches e and6 form an interlocking engagement of them as may be desired.

On cross-bar a along side of the slot link 6 is pivotally suspended alatch member f which carries a pivoted dog 7' supported thereon by thepivot pin 7. the dog are formed with cooperating jaws 7, f to engage orpass. around a horizontal pin 0 which is detachably and adjustablyclamped to the slot 0 of the weight arm 0.

Suppose it be desired to pass a belt from the driving pulley b to thecentrifugalpulley over the tension pulley a. In that case the.weight-arm is easily'lifted by seizing its forward or weight end 0 andraising it with one hand while the pivotal dog 7" is opened to allow thelatch swing into interlocking engagement around the stop pin Eitherbefore or after securing the latch the link 6 is raised to disengage thecross-bar 0L from-the forward I notch e and the pulley frame is thenswung mg frame,

tothe rear into engagement with the rear notch 6 The pivotal latchconstruction prevents the weight-arm I down while the notched engagementof the link 6 with the bar a of the frame holds the pulley wellretracted from the normal line of the belt so as to afford ample roomfor passing the belt over the outer pulley and lacing or fastening itsends while the pulley is in thisinoperative position. After the ends ofthe belt are fastened together the latch mechanism f. is released fromthe weightarm to allow the weight to press the pulley forward againstthe belt so "as to take up any slack or stretch in the belt, the linkhaving. first beenshifted to its forward position of interlockingengagement with the movable pulley frame.

It will be seen that the construction described aifords a single'rigldconnecting link by which the weight 1 danger of accidental release orbuckling while the pulley frame itself is easily and quickly shiftablefrom operative to inoperative position by merely raising the front endof the link to ]permit engagement with the other notch. oreover, theparts are all operated conveniently from the front of the machine by theattendant where they are most accessible to his reach and where,moreover, the application of the least effort is required to effect theshifting movements for adjusting the mechanism.

What we claim is:

.1'. In an automatic belt tightener the combination of a movable idlerpulley supportan independently supported weight-arm, a link pivotallyconnected at its rear end to an appropriate part of said weight-arm andhaving at its forward end a plurality of notches arranged to engage Thelatch and swinging supporting mechanism to I bination of the swingingengaging idler pulley, a weighted lever piv-' from dropping transmittedwith increased leverage to the pulley frame without 'the lever israised, 'scrlbed.

and position said pulley frame and to keep up the slack thereof,scribed.

2. In an automatic belt tightener the combination of a belt engagingidler pulley, a

frame therefor, an actuating lever for pressing the pulleynorsubstantially as .de-

.mally against the belt to keep it taut, a

connecting link one end of which is pivotally connected to the actuatinglever the other end of said link having direct adjustable engagementwith the pulley frame in order to transmit power from the actuatinglever to the pulley. frame and to position the pulley at differentdistances from the normal path of the belt, substantially as described.

3. In an automatic belt tightener the comframe and its belt otallysupported to allow its free end to drop by gravity, a slotted link oneend of which is pivotally connected to a short arm of said lever, theother end being formed with a slot having a plurality of pin-engagingnotches, and a pin mounted in the pulley frame to pass through either ofsaid notches whereby the movement of the weight lever is transmitted tothe swinging frame, substantially as described.

4:. In an automatic belt tightener the combination of the swinging frameand its pulley, an actuating lever for positioning the pulley tomaintain tension against the belt, a connecting link pivotally connectedat. its rear end to the actuating lever and at its forward end havingadjustable engagement latch when the free end of the actuating lever israised, substantially as described.

' 5. The combination of the swinging frame 'and'its idler pulley, a'weightarm pivotally said slot in position to engage i mounted to movethe pulley normally into tension engagement with the belt, a linkpivotally connected with said lever and having adjustable connectionwith the swinging frame, a pivoted latch mounted on said swinging frame,a pivoted dog carried by said latch, a locking pin mounted on said leverin position to be engaged andheld by said latch and substantially as de.6. The combination with the swinging frame and its'idler pulley, aweighted lever pivotally mounted adjacent thereto, a con necting linkpivotally attached at one end to said lever and at the other having anadmounted on the frame in position to engage dog when the free end ofand a dog pivotally connected therewith and provided with a projectinghandle said dog and latch being pivotally recessed to form aninterlocking engagement member-carried by said lever, substantially asdescribed.

In witness whereof we havehereunto set out hands this 29th day of July,1919.

GEORGE N. GODDARD. FRANK A. SMITH. V

with the locking 15

